1. Field of the Invention
The present invention relates to a variable lift height valve driving device, and more particularly to a variable lift height valve driving device which drives a valve of an internal combustion engine, varying the lift height of the valve depending on the driving state.
2. Description of Related Art
In the art of automobile engine, it is generally known to vary open/close timing of a valve depending on the driving state, namely, the engine speed and the engine torque. It is also known to vary the lift height of the valve depending on the driving state in order to improve the engine output and fuel consumption more.
In such a conventional variable lift height valve driving device, each cam shaft for driving each valve has a low-speed cam and a high-speed cam, and rotating forces of the cams are transmitted to the valve via a center rocker arm and a side rocker arm respectively.
Since the conventional device requires a plurality of rocker arms, the device becomes large. Further, since a mechanism for combining/separating the center rocker arm and the side rocker arm is necessary, the structure of the device is complicated.